Process of making helical rolls.



G. S. LOCKWOOD.

PROCESS OF MAKING HELIGAL ROLLS. APPLICATION FILED AUG. 21, 1909.

958,144. Patented May 17, 1910.

i To all whom mag ransom:

; STA ES. PA ENT- men; f

cmms "s; Locnwoon, or Nnwhnx, NEW messy, ass'reno'ri ro warehouse? Jasm ne comm,ror mmmson, NEW JERsEfzfgegfBrogA .Be it known that I, Cmu'znns SL001:-

lwoon; a citizen'offthe United States, residing at '289 Market street, Newark. county of.

,Essex, and State of New 'J'crsey, have in- :veuted certain new and usefu 'Improvemenis in Processes of Making Helical Rolls,

fully described and represented in the following specification and they accompanying drawings, forming a part of the same.

The object oflthe present invention is'to .ii nprove the manufacture of helical rollsfor uniformdiameter.

use in roller hearings, in which construct-ions the rolls require .for their mostperfect operlation to be trulyeylindrical in form and of The difficultyof produe-' ing such rolls is "greatly increased where the .rolls require tohave a small bore-in pr0por-- tion to their diameter so' that the COllS may haves uflicient thickness .to sustain a heavy load.

are formed by winding a strip side of the strip. anc

In the present invention, the helical rolls upon aman drel whose diameter is relatively small, so that the coils have considerable inclination across the axis .of the mandrel.

To wind a fiat strip upon a. mandrel at any considerahle'ai le, contracts the inner extends its outer side, and produces a shallow tronglrshaped cross-f section, which has heretofore caused a ridge on the roll, that required grinding to re- 1nove, nnless the rolls ire-reused for a grade of bearing in which perfect rolls were not required. here the strip is thin in relae is less prominent, evir out as the strip is made .thicker. The contraction also widens the inner side of the strip.

Since the helical rolls were first invented.

for roller bearings, thestandard ofqualit-y in such hearings and tlieloads imposed upon th'exnhave greatly increased, and an accuracy of form and ht is now demanded which was not required at'that time. as the roller bearings are now exlonsively used for. automobile axles, and in Theprcseiit invention is designed tofmcet these requirements by a process 0f 1llflnllfa0 j luring helical rolls which operates to'extend 'rnocnss' or mine i Specification time; recent" .Bfififlfi 1 Application filed August 21. 1909i 1seriai'mh'siaaicii red e;

form which" is" require feet roll.

I the strip-Ens woundmponthe and toehan e its crdss'section so.- thatli tinayi I adapt iitsel icompletely to'fthem-cylindriea percylindrical roll by winding a at s'tripnpon';

ate 5- a mandrel are illustr in the. annexed drawingyin'which+ Figure 1 shows'a perfect a the improved" processg'Fi'g. 2 is a,;1ongitudinal section on line 2 -2- in Fig: l, showing;

the correct form 0f the strip' lwhich fits it to the mandrel andfmakes its 'exterioi'i-cylin drieali; Fig. 3- is ya *planilof ajii'rolli artly wound upon a"'mandrel "extende :suffi-; cient l'y to fit'tt'hemandrel -iperfeotly,; Fig. 5 lis'an end .view-{ofthe 5 seine with. l l which storm. the coils} I Fig."i'5jf' show y the mandrelfwith-a sectio "oi'ztll ollgiandithe str1p,' when the-strip: not tended;v and 'Fig; 6"is' a} 'la'ihof-afde'fectireto spiral ridge-at the joint"-.ot theebils' -m 1=6faperfeefiiei lindrical form and :unitonn diameter; Fig. 2 showing the close contact of ther- SIXCQGSSIYG the-tools l was with the nandrel, 1producingan exterior cylindrical shape; The; bore .of the roll is one half its exterior diameteljthus re-' quiring a "strip quite thick in relation .to its width-which is neeexarily limited by the size of the roll.

In Fig. 3', the strip 'b' is shown wound into coils 0 upon the'niandrel '(Z, the strip. a

preaching the mandrel 'lan entially at t e point e. In winding a thicd g strip upon a small mandrel, theresistanee of the strip is so great that. the torsional strength ofthe mandrel would'not b'e sufiicient alone to nind the roll; andthe primary end oflthe .strip; is thereforeplainped or locked to the chuck that carries the mandrel, as indicated bfthe scre vab in Fig.3. Theron 'tion of ,the chuck thus produces an end all or tension upon jthe strip during the w iole winding operation, which isthe only force that draws thestrip through the rolls. Such all elongates or extends the strip'at the iteof the rolls. i a

supon the line iifia-in Fig. 4; which is ninety degrees from the tangential point Q,

,the' st-ri is fully-bent to the eurre'of the .rolh-Hn ;l f1S cross-section-fif the strip is not dedf hecpmes trough-shapedas shown .ndithe strip must be actually A ogerating' chuck- Suchforce reduces the t 'ckn strip thus therdrawing ofthestrip mandrel d, which rolls may :befpperated to reduce the of the stu to any de-.

,gree as it is formed i'ntothe co s.

' inch diameter upon a slender mandrel only sional strain if it were revolve'd'continu- 'o'usly at the same. speed as the headof the the coils to tension wherethey areformed .fromtheStriP- T i v respectively upon the upper-and lower-sides to turn and adjust 'itse -tatin the strip around a loose mandrel changed in form to fit the mandrel-properly. The. eigree of concavity in the strip is ekags gerate toshow it clearly, in Figsj and ,6; It isevident that tension upon the strip at the tangential point where it touches the mandrel willfoperate to pull the'stri into of the strip down friction and tension upon the strip. uch tension mayalso be produced by operating rollers upon the strip with sutficientforce to reduce its thickness and extend its length under the pull of the' ess of the stripv as it is wrapped uponthe mandrel, and the thicker portion of the through the rolls,'and subjects the metalin Fig. 4 shows .rollersti of the no as they arel wound upon the A stretching of the strip results from such reduction of its thickness, and causes the metal reduced by. thefforman '-'rolls to crowd forwardl around'the man el adjacent to the l ormedcoil's audit the head of the mandrel and the head of the strip be clamped together or' otherwise held. in a fixed relation upon the chuck, this forward crowding of the metal causes a great deal of needless friction, which I obviate in the, present in'- vention by winding the strip entirely by force applied to its own head; and not driving the mandrel at-all but leaving it loose if within the coils as the pressure upon the coils during the form ing operation may require.

Such a method of formin the coils not only obviates friction but one les me to positively wind 8, long -series of coils 3/8 of. an

3 /16 of an inch iameter which would have no torsional stren h suiiicient to wind the coils, and would subjected to great tor- The method of-forming the coils by rogreat y facilitates the .nanufacture of spirally coiled rolls, as the use of a loose mandrel makes the pull of the strip effective in stretching the metal ofthe strip where front-rest i and-to hold it in contact therewith during thewinding operation. The

pressure of the coils against the front-rest is also increased if any longitudinal tension be a plied to the strip 12, thearrangexnent who y avoiding the necessity of any rest at the op osite side of the coil, and the labor I of shi ting such rest backwardly to disengage the com leted roll when wound upon the mandrel. l3 using only a single rest '5 at the front of the coils; the mandrel, the coils, and the strip can'be manipulated with much' greater. faclhty when commencing to wind a roll and when removing the finished .coil from between the rollers 'g and h which are; somewhat opened or separated"when making such removal. All these advantages are [secured by locating the center of the mandrel and coils at oneside of the line 2-0:, joining the centers of'the rollers g and Jtwhich enables one rest to support the ooils' completely during the winding operatron.

. From the' above description it will be understood that the demand for thicker and stronger rolls necessitates the use of thicker stri s and 'the formation of a relatively sma bore in the roll ;;to give it the required resistance to compression when in use. A bore one half the diameter of the roll is now common, which proportion for the strip tends not only to roduce trough-shaped coils, but also to to uce a trapezoldal crosssection in the co 5, as shown In Figs. 2 and '5. The upsetting of the strip u on its inner side widens it at both inner e ges, but the pulling of the coils edgewise between the rollers g and h '(by the advance movement of the mandrel) crowds the metal over to the rear edges of the coils, and leaves one edge of each coil nearly square. These ef- .fects are produced by the use of a strip having'square or rectangular edges primarily, which form of strip permits'the formation of a more perfect cylindrical roll.

.The tra ezoidal cross-section is not detricmental to the rollel, but a trough shaped coil destroys the c lin rical form unless corrected in some ectualmanner;

The method of manufacture herein set forth thus changes a rectangular strip coils'of t apezoldal cross-section, while it simultaneously changes the natural trough: shape of the, coils to a true cylindrical form, thus causing two changes in the cross-sedtion of the metal.

metal andsimultaneously compressing the with closely adjacent coils,

This method of manufacture is a great improvement in'the art of making helical rolls,

as the use oi'thick stri s to make extra heavy and strong rolls ten s upon th'rolls much greater in proportion than ,was heretofore common. The means employed in present invention are wholly immaterial, as the invention consists in the changing of the cross-section of the strip coils, and in the steps of the process which are new inthemselves.

Hazing-tlins set forthThe natureof the invention what is claimed herein is:

1'. Theprocess of forming helical rolls which conslsts in progressively .bending into coils a strip of successive coils while positively extending to produce ridges practicing the -cessive coils as it is woundmt'o.

the length of enc to form I trough-shaped coils -1s obviat as set forth.

. v2. The process of formingfhelicaljrolls,

which consists in winding astrip of eater length than thickness, with such w; th applied to a mandrel, and compressing the' sucbelow the normal thickness of the stri while positively extending, the

length 0 the strip where wrapped upon the mandrel. r v F In testimony hereof I have hereunto setmy hand in the presence of-two subscribing wltnesses. I a I A p CHARLES vs. LOCKWDQD.

Witnesses: 1 a

'J. W. Gntnms'smr, -'j 4 Tnozgus S, CRAN v the metal, whereby the tend- 

